


Sorry, I Should Have Knocked

by fictionalthirst



Series: Catching Feelings [2]
Category: Final Fantasy XV
Genre: Casual Sex, Caught in the Act, Jealousy, M/M, Promiscuity
Language: English
Status: Completed
Published: 2020-11-24
Updated: 2020-11-24
Packaged: 2021-03-09 19:01:43
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,900
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/27701081
Author URL: https://archiveofourown.org/users/fictionalthirst/pseuds/fictionalthirst
Summary: Sequel to "Can I Take Your Order?"Gladio's still kind of reeling from his and Prompto's 'dinner date', when he has the day from hell.Prompto's out there living his best life, until an embarrassing mishap leads to a realization.
Relationships: Gladiolus Amicitia/Prompto Argentum, Prompto Argentum/Cor Leonis, Prompto Argentum/OC
Series: Catching Feelings [2]
Series URL: https://archiveofourown.org/series/2025941
Comments: 8
Kudos: 48





	Sorry, I Should Have Knocked

**Author's Note:**

> So this fic has some Cor/Prompto, and obviously the guy is old enough to be Prompto's dad, and also is his superior in the Crownsguard, so if that sort of thing isn't your cup of tea, I don't recommend continuing. :D

Gladio watches Prompto, sometimes, ever since their _quote-unquote_ date at the drive-thru last week. Notices a lot more the blond’s behavior with his fellow Crownsguard trainees and even some of his superiors. Where before Gladio saw an abundance of friendly energy, he realizes now that there is just the slightest spin on the blond’s behavior that signals amorous intent. A subtlety that Gladio has never been able to practice on his own. 

It’s not disapproval that Gladio is feeling when he sees Prompto lean just slightly into his hand-to-hand partner’s space with a soft, enticing smile. Gladio can’t judge flirtatious behavior, considering it’s at least thirty percent of his own personality. It’s something else… something a little more _covetous_. Which sparks a judgement that Gladio reserves for himself alone.

They hadn’t even gone back to his place to sleep together that night. After they sped away from the drive-thru, Prompto voraciously dug into his half of the food with a grin and a bounce in his seat. He suggested they park up at a nearby scenic overlook to the ocean beyond Insomnia’s eastern wall, a pretty terrace just off a highway ramp that had been sculpted with trees and fountains.

_“We’ve got, what, three months until we’re outside the wall?” He’d asked, his purple eyes sparkling with the reflection of the lampposts all around the parking area. “I can’t imagine what it’s like out there.”_

_“Wild,” Gladio had answered, trying to enjoy his hamburger, his gut burning with the guilt of letting Prompto have his way with him but having not reciprocated yet. “Gonna have to get you trained up in survival, too. Luckily, I’m an expert.”_

_“Then I’ll just leave it to you to take care of us out there,” Prompto joked, sticking out his tongue. “Iggy’ll do the cooking and cleaning, You’ll make sure we’ve got shelter and fire, and Noct will sleep through it all. I’m just there for comic relief.”_

_“I don’t think so,” Gladio warned. “You’re gonna pull your weight out there.”_

_“I’m kidding, Gladio,” Prompto chuckled. “I’d’ve thought that after an orgasm you’d unwind a little.”_

_“Mm,” Gladio grunted, and refrained from commenting. An awkward silence settled over them like a blanket in too-warm weather. Stifling._

_“Ahhhh, thanks for the food,” Prompto said, backing off the subject of the intimacy they’d had. “I’m full and getting sleepy now. Wanna just take me home? I’ve got early training again tomorrow and I don’t want to screw up. Cor’s overseeing us.”_

_“I’ll be there, too,” Gladio nodded. “Last round of observation before the final cuts.”_

_“Then I’d better bring my A-game,” Prompto grinned. “I’m over on-”_

_“Seventh and Zirconia,” Gladio finished, and turned the key in the ignition. “I gotcha.”_

That same bright smile is beaming at Calidus, a redheaded trainee about Prompto’s age. Their upper arms are touching as they chat, waiting for instruction from Cor to go and check their standing in the final round of cuts.

Prompto’s body is pointing toward the taller boy, whose elbow keeps playfully shoving at Prompto’s, who playfully pushes back. From an outside perspective, it would look like two young guys messing with each other, their fighting energy up and ready and needing an outlet between drills. It’s the angle of Prompto’s hips that tells Gladio a different story. Just a slight indication that their energy is less friendly and more… amorous.

It doesn’t make sense for him to feel jealous, and that thought makes anger simmer in his gut. Before last week, Gladio hadn’t ever considered the possibility that Prompto, Noct’s scrawny buddy from high school, would have even kissed him back, let alone go down on him in his truck. He’d fantasized about sex with the guy a few times, but it wasn’t emotional at all. Pure physical attraction.

Gladio wished he could suss out the reasoning behind his jealousy so that he could stamp it out and go back to normal. It wasn’t like any of his other sexual partners inspired this kind of feeling before. He’d happily watched as a couple of them carried on their own affairs _together_ after they’d departed his company.

When the training ends, and Gladio sees Prompto lift up onto his toes to whisper something in Calidus’s ear, he almost barks out an order for the blond to come over and do extra pushups for not paying attention - before his _fucking brain_ takes back over and realizes how _godsdamn_ insane he is behaving.

If Prompto wants to have casual sex with his friends and collegues, where is it Gladio’s business to stop him?

__________________

Prompto’s been flirting with Calidus for the better part of the month, and the larger guy is finally showing signs of making up his mind about whether he wants to hook up. Training this morning had been fun and flirtatious, and when they had been dismissed, Prompto suggested going back to Calidus’s place for “lunch”.

Bent over Calidus’s kitchen island, the larger guy jammed to the hilt inside him, Prompto smiles into the tile under his cheek and presses back, eager.

This was what had been missing with Gladio last week, Prompto sighs, gasping as Calidus hits his prostate with deadly accuracy. Prompto wishes that he could have been a bit more demanding that night, but he still feels a bit guilty for forcing himself on Gladio. Considering his lack of response to the blow job, Prompto’s pretty sure he should steer clear of the Shield for a while and give him some space, then apologize for making things weird. After their kissing in the Citadel gyms, Prompto thought Gladio had been down to fuck. But after the drive-thru, the older guy had been nearly silent and uninterested in flirty banter.

Shame clings to his guts like tar, and it slightly softens his erection, despite all of Calidus’s efforts behind him. He tries to shake the thoughts from his mind and concentrate on the task at hand. Calidus is giving his best effort, and it would be rude to think of someone else while they’re engaged.

Focusing on the sensations and the roll of Calidus’s hips, Prompto’s cock regains its ardency, and he widens his stance, hoping that the length hammering into him will reach new depths.

Calidus isn’t half as well-endowed as… others Prompto promised he would stop thinking about, but he’s getting the job done. Prompto is just a size queen. It’s something he can admit. To himself. Not to his partners, who rarely measure up, so to speak.

His mind wanders to the length he tried to force down his throat in the comfortable cab of his friend’s truck - and oh, he can’t trick himself into _not_ thinking Gladio’s name, it’s useless - and he gasps, imagining _that_ monster making room inside him. How it might not even fit all the way. How instead of jerking Gladio to completion, he should have gotten them to drive to his underground garage so Prompto could bounce in the big guy’s lap until they _both_ came as hard as he’d made Gladio.

The memory of that eruption of come under his palm and the rapidity of Gladio’s pulse in his cock sends Prompto over the edge into his own hand, and shortly after, Calidus cries out in completion, too.

The larger guy pulls out slowly, and Prompto turns around with a grin, trying to wipe the shameful memory of cresting with Gladio on his mind, rather than his current partner.

Calidus tugs off the condom and ties it, dumping it in his trash before pulling Prompto into a messy kiss.

“Let me drive you home?” Calidus asks.

“Nah, I’ll call a _Floht_ ,” Prompto smiles against him. “You rest up. You worked hard.”

They chuckle against each other’s lips, kissing one last time before tugging their clothing back on. Prompto waves a little before slipping out of the door, the cool early summer night calming and comfortable.

He fires up his phone again to use the ridehail app, and finds a text message from Cor, his heart skipping violently against his rib cage with surprise.

 **Leonis:** I have some office hours at ten a.m. tomorrow. Shall we meet to discuss your progress?

 _Hmm,_ Prompto smiles. _It’s been a long time._

 **Prom:** you bet, sir.  
**Prom:** i’ll be there at 9:59 sharp.  
**Prom:** ;)  
**Leonis:** See you then.

___________________

Gladio is having a _morning_. First he has an uppity recruit backtalk him in basic heavy weapons training, to the point he has to put the guy in his office for twenty minutes to cool down. Then, a burst pipe in the showers becomes his to attend to after he happens to be the ranking officer nearby. Now, he’s busted down to delivery boy as he makes his way to Cor’s office at all of ten fifteen a.m. to deliver the invoices for the repairs. Which are likely to set the Immortal’s shoulders to that calm but intensely uncomfortable glare, considering the cost to the crown that will likely come out of the ‘Guard’s budget.

He storms down the hall, usually friendly trainees moving in his wake, most likely due to the storm raging across his face. He hates getting a rough start to the day, especially after a night of shitty sleep. It’s a recipe for disaster, and Gladio wonders if he can just reset the day instead of face Cor’s cold wrath over the bill in his hand.

The Immortal’s office is at the far end of the Crownsguard Officers wing, in a rather lovely piece of architecture that overlooks the courtyard and fountains. Gladio’s office, in comparison, is nearer to the gyms, and he’s just a little bit jealous of the privacy afforded to the Director of the Crownsguard, all the way out here, nearer to the outside world.

Cor’s door is shut tight, which is odd, as he’s such an open-door kind of man. Especially this early in the morning, when he is usually doing paperwork and setting the schedule. Even if he’s gotten up to get himself some coffee, he generally leaves his door ajar.

 _Hm,_ Gladio stares at the closed portal and debates whether he wants to come back later. The opportunity to dump the invoice on Cor’s desk and scram is overwhelmingly attractive, so he fishes out his keyring and lets himself inside with a sigh of exhaustion that is far too early for the time of the morning.

He’s not sure what he had been expecting when he pushes his way into the room, but to find his boss, Cor The Immortal Leonis, fully dressed and balls deep in Prompto - the tiny blond’s legs thrown over the Director’s shoulders as he’s splayed completely bare across the mahogany desk - it’s a shock, to say the least.

Both of their heads snap to the door, Prompto’s comically upside down, and Gladio almost can’t move for a moment, his entire nervous system short-circuited and frozen. Nothing computes.

“Six,” He finally utters, and pulls the door closed behind him as he exits the room as quickly as he can reasonably manage. He leans against the closed slab of wood and tries to file his thoughts into order, but nothing adds up, nothing can be shuffled into the appropriate location in his system, and so he mechanically pushes his key back into the knob, locks the door once again, and makes his way to his own office.

He’ll deliver the papers later in the day. Perhaps later in the week. With his resignation, because how is he going to face his boss ever again?

___________________

“Shit,” Prompto says, looking back from the door to Cor’s cerulean eyes. They’re as tired and calm as usual, and Prompto kind of can’t believe it. If anything is going to ruffle the Immortal, Prompto expects it to be this situation.

“Gladiolus isn’t one to gossip. I’ll speak with him about it later,” Cor says, adjusting his footing, driving himself a little deeper and startling a sound from Prompto. “Unless you want me to stop?”

“No, no,” Prompto gasps, trying to breathe with the way he is so thoroughly pinned under the older man. “Definitely don’t stop. I’m good. _We’re_ good.”

“Excellent,” Cor agrees, and resumes biting at Prompto’s neck and collarbone, just as he had been doing before Gladio opened the door.

 _Well, if things weren’t ruined with Gladio already, they probably are now,_ Prompto thinks, and lets himself sink back into the moment with Cor, who is absolutely destroying Prompto’s ability to sit for the next few hours. Which might be an issue considering he has meditation after lunch.

“This isn’t doing it for me,” Cor says, grunting a little. “I want you to ride me.”

“Yes, sir,” Prompto breathes, his flagging erection regaining its strength with the command.

Cor slides Prompto’s legs from his shoulders, letting them lay in the crook of his elbows instead, as he lifts Prompto from the desk and settles them in his chair without slipping from within him even slightly. The show of power makes Prompto a little dizzy, but he recaptures his faculties enough to rise up on his knees and re-seat himself energetically, earning a rough groan from Cor’s throat. The chair is only just large enough for Prompto’s knees to wedge themselves between the arms and Cor’s thighs, but it’s plush and leather, so it’s not as uncomfortable as it would be if he was trying this with Gladio in his office, the shitty task chair no match for both of their combined weight -

 _Damn it,_ Prompto groans, thinking about Gladio again. _What the hell is up with that? He’s just **Gladio** \- Noct’s Shield, the guy that constantly harrasses me to be better in training. He’s hot, sure. And has a monster cock. And he’s really funny, as well as kind… it was pretty cute how worked up he got over the thought that I wasn’t prepared enough for the road trip - _

“Oh,” Prompto gasps, realization hitting him like a bucket of ice water. “Oh, fuck.”

“Don’t stop,” Cor breathes, his eyes closed and head tilted back, unaware that Prompto’s outburst was about anything other than their coupling. “Faster.”

Prompto complies, but it’s almost on auto-pilot, his mind occupied by the crushing weight of the knowledge that he _likes_ Gladio. And maybe Gladio _likes_ him back.

Or at least, did.

Cor’s warm palm encloses Prompto’s cock in his grip and the blond arches into the touch, his focus realigned to the moment. The expert manipulation of his flesh completely rips thoughts of Gladio from his head, and he pistons his hips harder and faster, Cor’s pelvis rising to meet each thrust as they chase completion.

“Come, Prompto,” Cor commands, and it sends an electric spark down to his groin that triggers him to erupt, his superior angling his cock up to spatter his orgasm all over his own bare flesh, rather than the finely pressed suit barely opened beneath him.

Cor picks him up, apparently remembering that they were positioned with Prompto on the desk for the purposes of not mussing his suit. Laying completely without any control over his muscles or faculties, Prompto moans weakly as Cor keeps hitting his prostate over and over again, wringing more pleasure from his already spent body. Finally, mercifully, the older man groans, his hips grinding one last time into Prompto’s unresisting flesh, and empties himself.

With one last caress down Prompto’s side, carefully avoiding the mess of his spend, Cor pulls out and quickly disposes of the condom. He hands Prompto several tissues to clean himself off, which he does with some difficulty due to his still pleasure-limp limbs.

Cor zips himself up and checks his watch. “Hm, went a bit long. Seems Gladiolus’s interruption was a distraction.”

“Yeah, just a little,” Prompto laughs. “Hard to come quick when your superior catches you in the act with another superior.”

“I will deal with the situation,” Cor promises again. “Don’t worry yourself over it.”

“Can’t promise anything but I’ll give it a shot,” Prompto throws a finger-gun at Cor, while pulling his clothes back on. “I have to run to Light Weapons training. I might be a little late.”

“Let me write a note for your instructor,” Cor offers, ripping a clean sheet of paper from his notepad and scrawling something quickly across it. “I will text you when I can. Train well.”

“Yes, sir,” Prompto salutes, lazily, his orgasm still not quite free of his flesh. “You know what I want before I leave, though, right?”

“Ah, of course, my apologies,” Cor says, and leans in to offer his pretty mouth to Prompto. The kiss is short and sweet, but it’s good enough for Prompto, who is desperate for affection on his best days.

“Bye,” Prompto smiles as he pulls away, and pushes through the blasted insecure door that prevented this from being one of the best times in months.

__________________

Gladio manages to skirt around bumping into Cor for the rest of the day. The invoices can wait to be delivered after six in the evening when Gladio knows Cor will be gone for the day. So, he’ll have to stay a little longer than usual at work. That’s fine. He’s sure that after a few days - maybe even a week - of avoiding his boss, he might get over the sight of him plowing one of their most junior trainees.

How exactly _that_ had come to pass, Gladio is curious about. Not enough to go digging into it, of course, but still. What exactly could have happened between Cor and Prompto to have led to _that_?

He’s a little late in the day for lunch, but it’s the best way to avoid running into _certain people_ , so he makes his way to the cafeteria with a significantly rumbling stomach. Thankfully, the mess hall is fairly quiet, mostly instructors and a few random trainees left to get their Crown-issued midday meal.

Gladio is only partway into his sandwich when a tray clatters down onto the table in front of him, settled there by just the spry blond he’s been trying to dodge all day.

“Hey, Big Guy,” Prompto smiles, hesitantly. “Cool if I sit here?”

“Yeah,” Gladio answers, just as tentatively. “Late lunch, huh?”

“Same to you,” Prompto grins. “I got a little ‘detention’ from my Light Weapons instructor for being late, even though I had a note.”

“Yeah, Tristus can be pretty stodgy,” Gladio nods as he takes another bite. Then without swallowing yet, asks: “Who’d give you a note for being-?”

 _Oh,_ Gladio blinks, chokes down the mouthful of his sandwich. _Right._

“Hey, so,” Prompto starts, low and leaning in, and Gladio wants to bail. Mentally grabs for a parachute cord on this conversation but finds only air. “I wanna talk to you about that. Cor said he was going to do it, but I don’t want to leave it up to him as if I’m a wayward youth that needs protecting or whatever.”

Gladio nods, but can’t meet Prompto’s eyes. He keeps mentally replaying the look of upside-down shock on the guy’s face, and he had been kind of hoping to just repress it for a while. He definitely hasn’t been expecting to be confronted head-on with it.

“It’s just, ya know, a fun thing that we do sometimes,” Prompto says, as though he’s talking about going on trips to an amusement park. “It’s nothing serious. And he’s not, like, using his authority to get me into bed-”

“Don’t you mean ‘onto desk’?” Gladio snarks, completely involuntarily.

Prompto blinks, eyes wide, and Gladio opens his mouth to apologize, but the blond breaks into a wild cackle that draws the attention of the few people left in the mess hall.

“Aw, man,” Prompto wipes his eyes and holds a hand to his stomach. He props an elbow on the table and leans his jaw onto his hand. “Yeah, that’s what I like about you, Gladio.”

“What is?” Gladio asks, eyebrows furrowed. Nevermind the fact that Prompto’s confessed fondness has squirmed hotly into Gladio’s gut.

“You’re funny,” Prompto smiles. “In kind of a mean way. I dunno.”

“Mm,” Gladio hums, ever the eloquent man that Prompto apparently thinks he can be. “Why are you explaining this to me, anyway? It’s your business what you do and who you do it with.”

“Yeah, true,” Prompto nods. “But I find myself caring about what you think of me. Whaddya suppose that’s about?”

“Beats me,” Gladio shrugs. “I’m not gonna judge you. I like to have a good time myself. I mean, case in point: last week.”

“Uh-huh,” Prompto tilts his head, crossing his arms against the table. “You didn’t really seem like that was much fun for you. Did I push too far? I thought you were into it, but looking back, maybe you weren’t and I was doing something really wrong-”

“No!” Gladio interjects, a bit loud, and draws the same amount of attention from the surrounding gathering. Quieter, he continues, “No, you didn’t do anything wrong. It was… great, actually. I’ve just never - it kind of made me feel inexperienced and _vanilla_ of all things. So I was kind of stewing over that.”

“Ah, okay,” Prompto smiles, sitting up a little straighter. “That’s totally a fair feeling to have. I’m just sorry to have been the one to make you feel that way. I… really like you, Gladio. You’re a good friend and… well I already kind of told you last week. Don’t want you to get a huge head over it.”

“Yeah, alright,” Gladio picks up his sandwich again, the knot twisting his guts finally loosened. “You know obviously the feeling’s mutual, right?”

“What does that mean, though?” Prompto asks, his soft face pinched with anxiety. “I have ideas, of course. But I don’t know what you’re thinking.”

“Well, why don’t you tell me your ideas and we’ll see how much of mine match up?”

“Hah, not fair,” Prompto grins, awkwardly. “I tell you something crazy like… ‘let’s get married tomorrow’ and then you’re like, ‘well actually I was thinking we could go out for some ice cream together’.”

“Alright, fine,” Gladio rolls his eyes, and throws a hand over the table to grip Prompto’s wrist. “If you want more, with me, then we both have to stop playing around with other people. For a little while, at least. I want to do this the right way with you, if we’re going to do it at all. Is that level of commitment good for you?”

“So you thought my proposal was a joke, then,” Prompto feigns melancholy, but just as quickly replaces it with a beaming grin. “Definitely works for me, Big Guy. Besides, not to get too graphic, but I’m pretty sure if I’ve got you, I’m going to be absolutely _full up_ with-”

Gladio leans across the table to press his palm against Prompto’s mouth before he can finish the rest.

“What am I getting myself into?” Gladio sighs.

Prompto wrenches the warm hand away from his face with both hands and exclaims, “Hopefully me, later tonight - ba-dum-ching~!”

“Is it too late to reneg on this whole deal?” Gladio groans, contemplating putting his head to the table in defeat.

“It absolutely is, dude,” Prompto smiles that innocent sunshine smile that is, as Gladio is learning, a total facade for a lust-demon.

It’s not so bad, probably.

**Author's Note:**

> catch me @fictionalthirst on twitter.


End file.
